Collaborative Research: Molecular-genetic Basis of Parallel Adaptation Driven by Coevolutionary Interactions

蝾螈通过分泌一种强大的神经毒素河豚毒素（TTX）来保护自己免受蛇等掠食者的侵害，但一些种群和种类的吊带蛇已经进化出了对TTX的抗性。这种抗性的分子机制是已知的，其中一个基因也是已知的，这为研究具有明显适应价值的性状的进化遗传学提供了极好的机会。这些研究将包括调查不同种群和种类的吊带蛇对TTX抗性变异的遗传差异，并对自然选择在抗性进化中的作用进行分子遗传学评估。多个人群中出现耐药性的原因可能有几个。这些是独立进化的多个阶段，在人群中传播，或者有共同的祖先；这些替代方案将通过分子遗传分析进行检验。这项研究将有助于解开新突变、重组和基因流动在解释表型多样性地理格局中的作用。该项目将有助于支持行为和分子遗传学的研究生和本科生教育。这些项目将通过犹他州立大学NSF ADVANCE项目、USU多元文化研究奖学金项目和Mountain Lake Biological Station REU项目促进少数族裔和女性参与科学事业。将继续发展蛇-蝾螈系统，作为一种模式，通过外展教育（类似于公共广播公司-电视最近在大众媒体上的材料和文章）和博物馆展览，向公众说明进化过程。

Newts defend themselves from predators such as snakes by secreting a potent nerve poison, tetrodotoxin (TTX), but some populations and species of garter snakes have evolved resistance to TTX. The molecular mechanism for this resistance is known, as is one of the genes involved, providing an excellent opportunity to investigate the evolutionary genetics of a trait that has a clear adaptive value. The studies will include a survey of the genetic differences underlying the variation in resistance to TTX in different populations and species of garter snakes and a molecular genetic evaluation of the role of natural selection in the evolution of resistance. Several factors could underlie the presence of resistance in multiple populations. These are multiple episodes of independent evolution, spread across populations, or shared ancestry; these alternatives will be tested with molecular genetic analyses. The research will result in disentangling the role of novel mutations, recombination, and gene flow in explaining the geographic patterns of phenotypic diversity. This project will help to support graduate and undergraduate education in behavioral and molecular genetics. The PIs will promote the participation of minorities and women in science careers through the Utash State University NSF ADVANCE program, the USU Multicultural Research Fellowship Program, and the Mountain Lake Biological Station REU program. The snake-newt system will continue to be developed as a model to illustrate the evolutionary process to the general public through outreach education (similar to the recent PBS-TV material and articles in popular media) and exhibits in museums.